Listen to Laura R. because she is right. I have been living in Japan for over 20 years now and have a Permanent Residence Visa. This does not entitle me to vote here or get a retirement pension, but that soesn't bother me. In other respects, I have the same rights as a Japanese National. I wouldn't change my nationality to Japaneses, although many foreigners do.
In my city, there are 5000 legal Brazilians, followed by Peruvians, Chinese, Koreans. In the lower percentages there are the Australians, Americans and British. Then there is a small class categorised as "others" which include Russians and Indonesians etc.
Then there some people who are here illegally; those are the ones the Japanese Immigration Office worries about and deports them if they catch them.
It is hardly worth the effort, as getting a legal visa is easy enough.
Most people agree that Japan is a better place all round due to the influence of people from other cultures (this includes the majority of Japanese who are very hospitable and kind.)
There has been a rise in the crime rate; especially petty crime, but nothing is perfect and most serious crimes such as murder are committed by Japanese themselves.
I think you must be referring to the Filippina "hostesses" whose visas were not renewed. The move was to target the pimps and the terrible conditions they kept these girls in, rater than to deport the girls for being aliens. It does seem a bit discriminatory as the streets of Tokyo are filled with Eastern European prostitutes and African pimps, but it was really the organized crime that was being hit and all the pimps were Japanese mafia.
I am sorry that the immigrants in Britain are behaving so rudely. But Britain had its problems when I was living there and most of them were caused by British vandals and hooligans and rapists and killers ... not a very good example for immigrants.
So now it seems there is a lot more violence and trouble and easier to pin the blame on minorities rather than clean up your own backyard.